[Overview of Status of Medical Device Registration and Quality Evaluation Requirements for Clinical Mass Spectrometry].

Mass spectrometry technology is becoming an important tool for clinical analysis due to its high specificity, high sensitivity and high multi-component detection capability. The current applications of this technology are mainly in liquid chromatography-tandem mass spectrometry (LC-MS/MS), matrix-assisted laser desorptionionization time-of-flight mass spectrometry (MALDI-TOF-MS), inductively coupled plasma mass spectrometry (ICP-MS), gas chromatography-mass spectrometry (GC-MS) and the related in vitro diagnostic kits. At present, the number of medical device (MD) based on mass spectrometry technology is growing rapidly, especially the number of LC-MS/MS and MALDI-TOF-MS registered MD products, and the standardization of relevant product quality requirements is also being effectively carried out.

Comparative study of plasma clearance of iohexol at different injection doses.

Background: Our goal was to compare the metabolic curves of plasma clearance of iohexol (Cl) at standard dose (5 ml) and contrast-level dose (50 ml).

Methods: The concentration of iohexol was measured at fasting state and at nine different time periods after a single bolus of iohexol injection. The interval between the injection of the two doses was longer than 24 hrs.

Repeated-dose (28 days) oral toxicity study in rats of an antiacne formula (BC-AF) derived from plants.

To evaluate the safety of a formula (BC-AF) consisting of the extracts of danshen (Salvia miltiorrhiza), loquat leaf (Glycyrrhiza uralensis), and licorice (Eriobotrya japonica), a preliminary 28-day, repeated-dose oral toxicity study was performed in Sprague-Dawley rats. Eighty animals were divided into four groups, with each group comprising 10 male and 10 female rats. BC-AF was administered once-daily by oral gavage at doses of 0 (control), 2.

713A, a new metabolite isolated from a fungal strain 713.

A new compound named 713A was isolated from the fermentation broth of a fungal strain 713. The structure of 713A was elucidated by spectroscopic methods. In the screening for interleukin-6 (IL-6) receptor antagonist, 713A exhibited inhibitory activity to the binding of IL-6 and IL-6 receptor with an IC50 value of 8.

4849F, a new metabolite produced by the Streptomyces sp. 4849 as an inhibitor of IL-4 receptor.

A new compound named 4849F was isolated from the Streptomyces sp. 4849. The structure of 4849F was elucidated by spectroscopic analyses.

Isoprenylated xanthones and flavonoids from Cudrania tricuspidata.

Further phytochemical investigation on the roots of Cudrania tricuspidata afforded a new isoprenylated xanthone, cudratricusxanthone I (1), two new isoprenylated flavanones, cudraflavanones C and D (2 and 3, resp.), and seven known compounds, 1,7-dihydroxy-3,6-dimethoxyxanthone (4), macluraxanthone C (5), cudraxanthones E, K, and L (6, 7, and 8, resp.), cudraflavanone A (9), and cudraflavone C (10).

Cytotoxic isoprenylated xanthones from Cudrania tricuspidata.

Eight new isoprenylated xanthones, cudratricusxanthones A-H (1-8), were isolated from the roots of Cudrania tricuspidata, together with ten known compounds, cudraxanthones H (9) and M (10), xanthone V(1a) (11), toxyloxanthone C (12), macluraxanthone B (13), 1-hydroxy-3, 6, 7-trimethoxyxanthone (14), cycloartocarpesin (15), artocarpesin (16), cudraflavone B (17), and kaempferol (18). Their structures were characterized by spectroscopic methods. Xanthones 5, 7, 10, and 12 showed inhibitory effects on four kinds of human digestive apparatus tumor cell lines (HCT-116, SMMC-7721, SGC-7901, and BGC-823) with IC(50) values of 1.